Palladium-gold catalysts are useful in the oxidation of ethylene or propylene in the presence of acetic acid to produce vinyl acetate or allyl acetate. Acetoxylation is commonly conducted in the vapor phase using a supported palladium-gold catalyst. Palladium-gold catalysts containing titania carriers are known (U.S. Pat. No. 6,022,823; U.S. Pat. Appl. Pub. Nos. 2008/0146721 and 2008/0281122; co-pending application Ser. No. 11/801,935 filed May 11, 2007). Acetoxylation is is preferably conducted in a fixed-bed reactor.
Commercially, titania is produced as a fine powder. To prepare catalysts suitable for fixed-bed reactions, it is necessary to form titania powder into particles, such as spheres, tablets, extrudates, and the like. Despite many efforts in developing methods for producing titania extrudates in the past, many are not suitable for commercial production because of their poor processibility. Therefore, there is a continued need to develop new processes for making titania extrudates that can be used as carriers for palladium-gold catalysts (see, e.g., co-pending application Ser. No. 12/653,563 filed on Dec. 16, 2009).